The Company have stated that, whilst it might have happened in the past, they're not going to bypass TP Captains in favour of jet F/Os when it comes around to filling jet Command positions. Therefore, at this moment in time, that must factor into your decision.
Secondly, will you have a Command or type-rating bond on the TP? That would only really be a factor if you were planning to leave in the next couple of years.
If you leave the jet behind temporarily to take the TP Command your jet time will always be there and valid, although some airlines have, in the past, discounted jet time on types such as the CRJ-200 and Emb 135/145.
Based on experience and decisions I've made in the past, I would recommend taking anything that's offered. Don't try and think about next week, next month or next year in your current Company because the big picture will have changed many times by then.
IMHO - take the TP Command, you'll enjoy the experience.