Half marathon training question

Train, maintain, taper...double up on the bits in the middle or plug in a couple of 10k's

I would repeat the last two weeks now, before you get too close to the taper.  It won't make any difference at this stage but you don't want to change the last few weeks of your plan.

As you have never done anything like this, it is probably best to play it by ear. The main factor is going to be how quickly you recover from the first half marathon. Effort, training, injury and weather will impact on this.

Early week 1, I would do a few slow recovery runs, and then depending on how you are feeling then build up some intensity / mileage afterwards.

I have done this sort of thing this year when I ran my first and second HM races with 2 weeks in between, Towards the end of week 1 I did a short tempo run, and then a long slow run of about 14 miles at the weekend. The following week was mainly easy runs, with another tempo session to liven things up.

As has been said, Tapering for a half is not for everyone (including me).  Let the recovery guide you. Some will recover in a day or two, others in a week or longer.

oops!

I think play it by ear is a good guide.  Best case scenario, you cope well with the training, in which case the added couple of weeks will be an opportunity to push slightly further on the long run mileage, or to at least repeat the 13 miler just before the taper, perhaps with a shorter long run in between.

And since you've not done it before, definitely stick with the taper plan.  A half is long enough that you want to go into the race not only with your muscles well recovered from training, but also with good energy reserves.  You won't hit the wall, as is a risk in a badly prepared-for marathon, but you still want to be well rested.