The Spring Update did not "fix the ability to tune up to 1Ghz", the Premiere was already capable of 1GHz.
What it did fix was the ability to decode and/or display copy protected MPEG4 (H.264) encoded video.
Are the Plus Package channels in the Pensacola/Gulf Coast market MPEG2 or H.264? Your market does not list many Plus Package channels currently, Are there more than listed?
You may still need to call Cox @ 877-820-8202 to have the Plus Pak channels added to your account.
You also must subscribe to the corresponding package
** Channel available with subscription to Cox Advanced TV Plus Package, Cox HD service and subscription to corresponding programming Pak or premium channel.
Plus Package Pensacola/Gulf Coast
1101 The Hub HD** (Bonus TV Pak)
1317 DIY HD** (Sports and Information Pak)
1342 Cooking Channel HD** (Variety Pak)
1900 SWRV HD** (Variety Pak)
1203 HBO Family**
1210 HBO West HD**
1212 HBO Latino HD**
1234 Cinemax West HD**
1248 Showtime West HD**
1262 TMC West HD**
1287 STARZ West HD**