I have a GMRS License and am currently studying for my Technician License. Once I pass the exam, can I use my GMRS Call Sign?
You will need to continue to use your GMRS on GRMS frequencies with GMRS radios and once you get it your ham call sign on ham frequencies.
The call signs for GMRS have a different format than ham radio call signs. From what I can see GMRS call signs are 3 or 4 letters followed by 4 numbers. Ham radio call signs are 1 or 2 letters, 1 number, and 1 to 3 letters.
Your GMRS license is only good on GMRS allocated frequency bands using GMRS equipment. Similarly, your Amateur Radio Service (ARS) license is only good on ARS allocated frequency bands using ARS equipment. When you pass your ARS Tech exam, wait until the FCC issue you (via the CORES) your unique ARS callsign before getting on air. You can't use your GMRS callsign on ARS frequencies and vice versa. Have fun!