Hi Carolina,
what you measured is Tag in Responsive mode. In this mode the DW1000 and MCU do not go to deep sleep. This mode is more suitable for demos or when consumption is not a problem. The BLE is constantly on and allows quick discovery.
In order to keep the Tag in sync with the slotted network it sync from time to time. When running at 100ms it can be actually more favorable because it does not need to sync… this is related with internal implementation.
If you want to achieve low power consumption, then switch to Low Power mode, i.e. disable Responsive mode.
Responsive mode is the same as “Low Power mode disabled” and vice versa. The naming is a bit confusing I admit.
Cheers,
TDK