MDL's contract specifies a maximum number of days on board in a year. I once pointed out that if we did the number of weekends we usually do, and got stuck in port for a few days on a 2 week holiday we were in breach, but they said it was there to prevent 'proper' liveaboards.
Not MDL I'm afraid but Haslar (Gosport) seems to be happy having some liveaboards. Informally they add to the security at the marina as extra pairs of eyes and ears.
Many of the boats we went to look at in Brighton Marina appeared to have been purchased as an inexpensive way of buying some decent accomodation in the area.
IMO what would not have been acceptable by marina's a few years ago....might just be accepted now, there are quite a few gaps in most south coast marinas at the moment. Especially if you have a large boat.... £££
I would imagine the ruling would give management the option to off-load undesirables.
We enjoy having civilised liveaboards, because of 'eyes and ears', but also they help berthing visitors, after hours and gives the place a lived in feel.
MDL seem to be the most anal of the marina operators when it comes to interpretation of rules and statutory regulations. Why on earth does MDL QAB deem it necessary to change the gate code daily!
Moving a family onto a live aboard marina yacht is often the trigger point for intervention from local marina management.
Another point to consider is water quality within a locked marina, I guess liveaboards could cause a greater problem here.
A locked waterway based marina could/would have issues with discharging grey water on a continual basis.
We have a 3.5 to 4.0 metre tidal variation and top quality amenities.
Also we have had a situation where a family with totally out of control younger children, caused no end of problems.
Even worse than that, is a person with a control freak personality, that moves into residence and tries to shape everybody to his way of thinking.
If you get the mix right, the system works well, as it does for us. It will be extra work for the manager, but if working short handed, good liveaboards are an asset.