The current Verizon situation for my smart phone and 2 jetpacks is:
Each device (yes the smart phone too) is limited to full 4G LTE up to 15gb. Yes, the smartphone is limited to 15gb when using it has a hotspot or tethered. After that 15gb limit is reached the speed will reduce to 600 kbps. The 22gb limit is correct for the smartphone, but not when using it as a hotspot. After the 22gb is reached it may be throttled depending on cell congestion.
There are other special deals out there, but this is mine as of right now.
My devices: Samsung Galaxy Note 8 (factory unlocked), 7730 and 6620 Verizon Jetpacks.