Sending Someone Else To Bid For You In TX

I read somewhere (can't remember where) that there is a relatively new law stating that an investor cannot send someone else to bid on their behalf at the Texas tax deed sales, and if they did the deed was void.

Has anyone heard about this? Or have any ideas on where I can find out? Are there any alternative options rather than actually traveling to TX (and incurring the travel costs when you can't even be sure you'll buy a property)?

Thanks so much for any advice you might have!!