The scenario:
0. Start with a tz.. address with some balance.
1. Change/Stake to custom baker X.
2. Wait for confirmation.
3. Change to custom baker Y.
4. The node responds with a hash like everything is OK, but the transaction never gets into the blockchain.
This happens only on mainnet. Is there any minimum time to wait (or blocks, or cycles...) between delegating and changing the delegate?
There is no minimum amount of time you must wait between switching delegates. What are you using to verify the operation was NOT included in the block chain? Check with multiple explorers to verify.
Why do you want to do this? You pay an operation fee each time you switch.
Also, if you submit to baker X at block 5, and then a snapshot happens at block 6, then you change to baker Y at block 7, you will be tied to baker X for at least 1 cycle because of the snapshot.
Keep in mind too that changing bakers requires a 7 cycle waiting period.
