if they are 6 weeks into flowering those buds should at least triple in size over the next two weeks and i would just let them carry on now until they are finnished. IMHO i'd say its too late to start messing about with them now.
i wouldnt let my plants dry for that long at all, especially at this stage as they tend to drink a lot more at this stage as you may already notice. i normally water every 2 days but in a pot that size i'd pour about 1.5 litres in slowly and make sure its room temp.
if you feed them now you wont have time to flush them so just keep watering and keep an eye on them i wish you all the luck. those buds will grow