When it comes right down to it, all upgrades... whether they are Second Life related or the technology industry in general... are forced to one degree or another. The methods used to force the upgrade vary and have different impacts upon the user base.
One possibility, for instance, is that LL incentivize the owners/managers to do their upgrade within a reasonable period of time... sweeten the deal for them a little bit in exchange for them doing the work monitoring, reporting, and if it is small enough in nature, to fix a problem with the upgrade (like an obvious typo in an upgrade script that may have brought the whole thing to a screeching halt). That's one level of force.
The one thing I learned during my time in IT... it's a great dream to have every piece of equipment running at the same performance level on the same software and firmware level. But, in reality, that's what it is... a dream. Hardware failures... variations within components used within servers... bad batches of hardware... poorly functioning communications between remote locations... all of these factors, which are out of LL or any services hands (usually), add up to the reality that equipment is often on different performance levels on different levels of software. It's a livable situation; not the perfect dream, mind you, but certainly a livable compromise between the dreams of the IT staff and the stability the users expect. Should this sort of dream be forced to the point where customers start withdrawing their presence, both physically and financially? Only LL can answer that.
All I'm suggesting is that for those owners/managers who are complaining about wanting/needing more control in providing the best possible service to their customers, LL should give them the opportunity to schedule their own upgrades. If there is a true spiriti of cooperation, those owners/managers know that upgrading their properties will be to their benefit and LL will recognize that they understand the owners/managers know what's best to retain their customers' loyalty.
Upgrading is by nature a forced activity. How that upgrade is managed and the level of trust and communication that is exchanged among LL, its owners/managers, and its consumers makes the difference between the process being a minor nuisance or a major kerfluffle.