Will there be a period of enforced peace - i.e. everyone in god mode - during the merger? It would suck if you were prevented from teleporting a city by being attacked.
At least 38 days until the merge, activate Plutus in all towns, build massive army 3 days prior to merge.
That wouldn't prevent the town lock in any case.
Anyway, I think at the start of the merge everyone is more worried about organising their own spots, alliance spots and all other jambo instead of slowboating some random guy.