I have created my own custom project based on the template ble app, porting over the relevant includes and settings in order to start fresh. Despite my section placement file and macros matching that of the example, I am met with significant linker errors:

I assume this is one issue causing multiple errors, so any help would be much appreciated!
<!DOCTYPE Linker_Placement_File>
<Root name="Flash Section Placement">
<MemorySegment name="FLASH" start="$(FLASH_PH_START)" size="$(FLASH_PH_SIZE)">
<ProgramSection load="no" name=".reserved_flash" start="$(FLASH_PH_START)" size="$(FLASH_START)-$(FLASH_PH_START)" />
<ProgramSection alignment="0x100" load="Yes" name=".vectors" start="$(FLASH_START)" />
<ProgramSection alignment="4" load="Yes" name=".init" />
<ProgramSection alignment="4" load="Yes" name=".init_rodata" />
<ProgramSection alignment="4" load="Yes" name=".text" />
<ProgramSection alignment="4" keep="Yes" load="Yes" name=".sdh_soc_observers" inputsections="*(SORT(.sdh_soc_observers*))" address_symbol="__start_sdh_soc_observers" end_symbol="__stop_sdh_soc_observers" />
<ProgramSection alignment="4" keep="Yes" load="Yes" name=".sdh_ble_observers" inputsections="*(SORT(.sdh_ble_observers*))" address_symbol="__start_sdh_ble_observers" end_symbol="__stop_sdh_ble_observers" />
<ProgramSection alignment="4" keep="Yes" load="Yes" name=".pwr_mgmt_data" inputsections="*(SORT(.pwr_mgmt_data*))" address_symbol="__start_pwr_mgmt_data" end_symbol="__stop_pwr_mgmt_data" />
<ProgramSection alignment="4" keep="Yes" load="Yes" name=".nrf_queue" inputsections="*(.nrf_queue*)" address_symbol="__start_nrf_queue" end_symbol="__stop_nrf_queue" />
<ProgramSection alignment="4" keep="Yes" load="Yes" name=".sdh_req_observers" inputsections="*(SORT(.sdh_req_observers*))" address_symbol="__start_sdh_req_observers" end_symbol="__stop_sdh_req_observers" />
<ProgramSection alignment="4" keep="Yes" load="Yes" name=".sdh_state_observers" inputsections="*(SORT(.sdh_state_observers*))" address_symbol="__start_sdh_state_observers" end_symbol="__stop_sdh_state_observers" />
<ProgramSection alignment="4" keep="Yes" load="Yes" name=".sdh_stack_observers" inputsections="*(SORT(.sdh_stack_observers*))" address_symbol="__start_sdh_stack_observers" end_symbol="__stop_sdh_stack_observers" />
<ProgramSection alignment="4" keep="Yes" load="Yes" name=".nrf_balloc" inputsections="*(.nrf_balloc*)" address_symbol="__start_nrf_balloc" end_symbol="__stop_nrf_balloc" />
<ProgramSection alignment="4" keep="Yes" load="Yes" name=".cli_command" inputsections="*(.cli_command*)" address_symbol="__start_cli_command" end_symbol="__stop_cli_command" />
<ProgramSection alignment="4" keep="Yes" load="Yes" name=".crypto_data" inputsections="*(SORT(.crypto_data*))" address_symbol="__start_crypto_data" end_symbol="__stop_crypto_data" />
<ProgramSection alignment="4" keep="Yes" load="Yes" name=".log_const_data" inputsections="*(SORT(.log_const_data*))" address_symbol="__start_log_const_data" end_symbol="__stop_log_const_data" />
<ProgramSection alignment="4" keep="Yes" load="Yes" name=".log_backends" inputsections="*(SORT(.log_backends*))" address_symbol="__start_log_backends" end_symbol="__stop_log_backends" />
<ProgramSection alignment="4" keep="Yes" load="No" name=".nrf_sections" address_symbol="__start_nrf_sections" />
<ProgramSection alignment="4" keep="Yes" load="Yes" name=".cli_sorted_cmd_ptrs" inputsections="*(.cli_sorted_cmd_ptrs*)" runin=".cli_sorted_cmd_ptrs_run"/>
<ProgramSection alignment="4" keep="Yes" load="Yes" name=".fs_data" inputsections="*(.fs_data*)" runin=".fs_data_run"/>
<ProgramSection alignment="4" keep="Yes" load="Yes" name=".log_dynamic_data" inputsections="*(SORT(.log_dynamic_data*))" runin=".log_dynamic_data_run"/>
<ProgramSection alignment="4" keep="Yes" load="Yes" name=".log_filter_data" inputsections="*(SORT(.log_filter_data*))" runin=".log_filter_data_run"/>
<ProgramSection alignment="4" load="Yes" name=".dtors" />
<ProgramSection alignment="4" load="Yes" name=".ctors" />
<ProgramSection alignment="4" load="Yes" name=".rodata" />
<ProgramSection alignment="4" load="Yes" name=".ARM.exidx" address_symbol="__exidx_start" end_symbol="__exidx_end" />
<ProgramSection alignment="4" load="Yes" runin=".fast_run" name=".fast" />
<ProgramSection alignment="4" load="Yes" runin=".data_run" name=".data" />
<ProgramSection alignment="4" load="Yes" runin=".tdata_run" name=".tdata" />
</MemorySegment>
<MemorySegment name="RAM1" start="$(RAM_PH_START)" size="$(RAM_PH_SIZE)">
<ProgramSection load="no" name=".reserved_ram" start="$(RAM_PH_START)" size="$(RAM_START)-$(RAM_PH_START)" />
<ProgramSection alignment="0x100" load="No" name=".vectors_ram" start="$(RAM_START)" address_symbol="__app_ram_start__"/>
<ProgramSection alignment="4" keep="Yes" load="No" name=".nrf_sections_run" address_symbol="__start_nrf_sections_run" />
<ProgramSection alignment="4" keep="Yes" load="No" name=".cli_sorted_cmd_ptrs_run" address_symbol="__start_cli_sorted_cmd_ptrs" end_symbol="__stop_cli_sorted_cmd_ptrs" />
<ProgramSection alignment="4" keep="Yes" load="No" name=".fs_data_run" address_symbol="__start_fs_data" end_symbol="__stop_fs_data" />
<ProgramSection alignment="4" keep="Yes" load="No" name=".log_dynamic_data_run" address_symbol="__start_log_dynamic_data" end_symbol="__stop_log_dynamic_data" />
<ProgramSection alignment="4" keep="Yes" load="No" name=".log_filter_data_run" address_symbol="__start_log_filter_data" end_symbol="__stop_log_filter_data" />
<ProgramSection alignment="4" keep="Yes" load="No" name=".nrf_sections_run_end" address_symbol="__end_nrf_sections_run" />
<ProgramSection alignment="4" load="No" name=".fast_run" />
<ProgramSection alignment="4" load="No" name=".data_run" />
<ProgramSection alignment="4" load="No" name=".tdata_run" />
<ProgramSection alignment="4" load="No" name=".bss" />
<ProgramSection alignment="4" load="No" name=".tbss" />
<ProgramSection alignment="4" load="No" name=".non_init" />
<ProgramSection alignment="4" size="__HEAPSIZE__" load="No" name=".heap" />
<ProgramSection alignment="8" size="__STACKSIZE__" load="No" place_from_segment_end="Yes" name=".stack" address_symbol="__StackLimit" end_symbol="__StackTop"/>
<ProgramSection alignment="8" size="__STACKSIZE_PROCESS__" load="No" name=".stack_process" />
</MemorySegment>
</Root>