Basically, what you have to consider is the fact that if the developer is more than three months late delivering the property (from the completion date specified in your contract) then they are at fault, not you!! And the most important factor, you do not complete before the LFO (Occupation Licence) is issued by the local authority. I would think that they cannot sue you, especially if they are late in delivering the apartment and, more importantly, not before the LFO is issued! Especially in the current climate in the CDS, with many "bad" builds (without building licences, etc,.) have occurred in recent times.
If your lawyer is pressing you to complete without all documents in place and much later than your specified contractual completion date, then your lawyer should be replaced!!
So just make sure you have the LFO in place and that everything is to your satisfaction, then complete - and not before!! Nobody can force you to do otherwise!!
In our personal experience, RyF didn't push at all to complete and most certainly didn't expect us to complete before the LFO had been granted. If for some reason that has changed, then that's surprising. They have always, from our experience, been most helpful. Although, saying that, they obviously have a lot of apartments to move, so maybe they are cutting corners now!! I would hope not!!