You should not need a sat connection to make a phone call but you will need to wait out the acquiring sat info when booting up. After connecting phone line, go to phone connection menu and select "Connect to to DVR service now" (might be worded a little different for 3.1.5). After call completes, look at Last Status and hopefully if will show "Pending Restart". Restart and you should get upgraded. It might take several calls over a period of days to get the upgrade.
You could also use InstantCake to re-image the HDD and get the upgrade that way. Another option is to replace the drive. You can get a pre-imaged drive from weaknees.com, dvrupgrade.com or eBay. All you need is 2 Torx screwdrivers (T-10 and T-15) to replace the drive.
You could also use InstantCake to re-image the HDD and get the upgrade that way. Another option is to replace the drive. You can get a pre-imaged drive from weaknees.com, dvrupgrade.com or eBay. All you need is 2 Torx screwdrivers (T-10 and T-15) to replace the drive.