Is anyone familiar with bridge letters in NetSuite? Is there a way to receive them for 2023 before mid-Jan?

As far as I remember they are issued even later. You can try and ask your account manager on the NetSuite side.

I thought you can open a ticket for bridge letters too

you can submit a request for documents like bridge letter. SuiteAnswer ID 69043

From within Account Centre, there is a privacy compliance tab, this gives you a link to create an audit request. Then they email you the pdf's in about a day or so.