Day sailing with wife and friends, and stuck in the mud (17nm trip 322nm total)

Went down to Dorset for a couple of nights and went out sailing with friends on Saturday. Motored west in the Harbour and then tacked up the Wareham channel. Motored up the Frome to Wareham, where we rafted up alongside a friendly motor boat and had lunch and a drink the the Granary Pub.A nice spot. Left rapidly when someone started rafting up outside us. We didn't want to get stuck (little did we know what was coming then).
We motored down the Frome and in the channel I turned up into the wind so we could raise the sails and have an easy run home. I concentrated on not banging into a starboard channel marker, not noticing we were on the wrong side of it until my wife commented that we weren't moving...
Got the sails down too late. We had slid onto the mud, which was too soft to either jump out on or to push off from. we were stuck, on a falling tide and we just had to wait for it to come back. 2 1/2hours later we got off. I now know that low water at the head of the Wareham channel is 45 minutes later than at Poole quay. Nothing moves slower than a watched tide.
We had the benefit of water ballast. We pumped it all out, which helped pass a bit of time, and meant that we probably got off about half an hour sooner than we would have otherwise. But all was well and we were back in time for dinner. We left the boat on the pontoon over night and I went back to her the next morning to clean off the Poole mud and put her back on her mooring.

This google map shows where we spent the afternoon doing a bit of unplanned bird watching (godwits and egrets in particular).

Further note: the hinged table over the centreboard came into its own. The board was firmly jambed when we floated off. Mud sticking the whole board into the trunk. My wife hinged it open and a good push on the blade forced it down and cleared the slot. Total action took less than half a minute.