BACKGROUND
So, I have a project that I am working on, the control panel of the Apollo 11 spacecraft. I finished modeling it and texturing and rendered an animation. It all was fine and ended up with a short video, no problem. Later I realized that in some sections the camera didn't stay long enough, so, pop back into blender, change some keyframes, voila. Render, then disaster strikes.
ISSUE
The time for a frame started at around 8 secs then ended up at about 5 mins. After watching it for a while the time steadily goes up as it gets further through the animation, there's also a lot of time going into "updating shaders".
ATTEMPTED FIXES
Tried changing tile size from 64x64 to 128x128 and 256x256 didn't fix. Prevented it from using my CPU, but didn't help. I've looked at task manager performance and only 1% of my GPU is being used, about 3% of my CPU and around 30% of my RAM. Maybe there is some sort of restriction in the settings? Any help would be much appreciated, thanks in advance for any replies.
HARDWARE
RTX 2070 - GPU
Ryzen 5 2600 - CPU
Gigabyte b450m ds3h - MOBO
Samsung 970 EVO - M.2 NVME SSD
Western Digital - HARD DRIVE
Corsair Vengeance LPX 32GB DDR4-3200 - RAM
SOFTWARE
Windows 10
Blender 2.8