Yep what you have said is correct, it's essentially a free year (or 2 if the timing is aligned) of your current status. A work colleague was in a similar situation of using the hold and as I read it, we calculated the best outcome for her to apply for hold start date to maximise this scheme and essentially when coming off hold you have a free year of your existing status.

Looks like your dates line up nicely where your elite was coming to an end anyway and you've just got maximum benefit of a few more years elite without having to do the hard yards, well atleast not the earning hard yards but with twins I'm sure you'll be doing the real hard yards.

Best of luck