Dummy's rights, Declarer's lead out of turn.
Where I play, if declarer leads out of turn either from his hand or dummy, dummy or defenders are quick to point out the error, whereupon declarer either withdraws the card played erroneously and leads from the correct hand or follows from the other hand if it is the same to him. The defenders' rights under law 55 don't feature!
Does this happen with you also?
If the defender/s draw attention to the erroneous lead they may be deemed to have asked for it to be retracted, so no further action would be called for, even though they are thereby giving up their right to accept the incorrect lead if it happens to suit them.
In the case of dummy, however, it has been pointed out to us that law 42B3 allows dummy only to prevent an irregularity, he cannot correct it after it has been committed. Quite rightly too, the way the law is worded.
Therefore, if dummy draws declarer's attention to the latter's lead from the wrong hand after the lead has been made, he is in violation of law 43A1(b), with the consequent restrictions listed in law 43B. Have you seen these being enforced?