On FreeDMR you can move to a new Talk Group without doing a 4000.
PTT for up to 3 seconds on the new Talk Group you wish to use.
Now you can TX and RX in that Talk Group.
Manual Dial 4000 Private Call transmit for up to 3 sec.
The repeater / hotspot will respond with a voice announcement “Not Linked”.
You can move to a new Talk Group without doing a 4000. Just call the next Talk Group and PTT for up to 3 sec.
Would be recommended to make a 4000 unlink channel. Add 4000 as a Private call to the radio. Set TG9 in the RX Group. Now when you get a GAP in RX you can PTT and unlink.