Yes they will honour price drops as long as your TA is prepared to do it for you. If you book with a TA X or RCCI will not entertain dealing with you directly.
Booked last week for Solstice and there is a price drop on all Balcony rooms and my friend June will benefit from this. Just waiting on the revised invoice from X. Drop of £140 No drop for me but I got an over 55 discount which was there when I booked. This has now gone and its back to the origional price for everyone. Gained £230 from the offer.
I usually check every few days just to see and yes as Graham says you need to moniter this yourself.
Any resistance from your TA just keep hammering away at it and they will be forced to sort it out for you.
Good luck
Sue