Are Their any Tube Preamp with Home Theater Bypass?

I am looking at this issue as well and found this helpful page listing both integrateds and preamps with HT-bypass:

It is updated but not complete (for instance it is missing Modwright).  I have considered moving my Schiit Freya plus to my AVR system, which does not have HT bypass but does have a passive mode.  Some problems I see with just using unity gain are 1) the fear of switching inputs without lowering volume, and 2) I believe that you cannot utilize an unbalanced input (from an AVR for instance) going to a balanced output to your amps in passive mode.  I could be wrong on this second point.

I have a related question.  If you want to incorporate a single subwoofer into both the HT system and 2 channel system, how do you accomplish that?  Do you simply have to use two different inputs into the sub?

Cary Audio SLP-05.  End game preamp. Has HT bypass. 

The TAD 150 Signature has it, if you can find one ( used only).  It’s passive, so the pre doesn’t need to be powered up.

Yes I have a McIntosh MX120 home theater preamp, with a McIntosh C2300 tube preamp. The C2300 has goes into bypass when the MX130 is on watching TV. Works excellent and love them both. Highly recommended. Although the C2300 has updated versions C2600 they all have bypass. 

I was in the same boat a while back. I didn't want to be limited to only amps with HT bypass. I decided to try a selector from Amazon,(SOLUPEAK P2 2(1)-in-1(2)-Out Amp) which does a great job and allows me to choose which amp feeds the speakers. It's a simple device and I have noticed no loss in quality. No issues with the tube amp and Marantz AVR after a few years. I actually swap between tube and some vintage SS in that system because it's made it very easy. It's a simple device and you could always upgrade the wire inside if you wanted to.