So I got a unexpected week off work

I did that at a training camp during a school break two weeks ago. You should be okay with getting in some extra biking (and maybe swimming) as it's low-impact. Make sure your seat if comfortable and use plenty of body glide if it's not a bike/seat you've been spending much time with lately. I would be extra careful about rest and recovery, though. It's flu season, and sounds like weather might warm up and cool down suddenly--the extra training stress plus unstable weather could make you vulnerable. Don't want to discourage you, but since that camp, I have been sick. I think I have done two runs and one swim since then.

Of the three areas of a triathlon, bicycling is the most forgiving. It also tends to reward lots of miles.