app_sched_event_put is not generating an event when concurrent connections and disconnections

Hi there,

I am designing a bridge application between different devices which uses BLE as central and peripheral to connect all them, the idea is have up 20 nodes connected each other, to keep alive that bridge between all my devices 

I am testing on my app multiple connections roles central and peripheral, but when I get more than 5 connections, the schedule on my application stop working, I mean it does not trigger more schedule events, for example, I use app_sched_event_put() to trigger a function when the softdevice have some time slot available, but it works if I have less than 5 concurrent connections, also after I got 6-7 connected nodes I am experimenting disconnections and reconnections

my settings:

NRF_SDH_BLE_GAP_EVENT_LENGTH 33
NRF_SDH_BLE_GATT_MAX_MTU_SIZE 247
NRF_SDH_BLE_GAP_DATA_LENGTH 251
ADV_INTERVAL 500
NRF_BLE_SCAN_SCAN_INTERVAL 500