First, thanx Merlin for the quick response!
...argh... there's two kind of comments to my question; Like Merlin said "continue with old schedule" and other opinion is that I should go with new schedule and if necessary, go down like an hour or so to get slowly back in to normal schedule... got...
My bitches have been into flowering for about 7 weeks and there's at least 2-3 more weeks to go - so the lights are 12/12 (8.00am to 8.00pm dark).
This morning the lights somehow stayed on about 1.40pm until I saw something was wrong. Turned the lights off and started to find out what to do...