I replied to somebody else here, with a similar issue.
I run also an Umbrel with HDD, not SSD, but in a NUC with Debian OS. I have no issue with “slowliness” as many here try to say.
Yes, SSD is faster than HDD, but that is not affected too much when you restart your node and is catching up.
Umbrel is recommending SSD for RaspPi users, so when you conect that external HDD drive through USB and a case, is a like a bottleneck. HDDs are NOT designed to be fast as external drives. Things are changed when you use them as internal drives, in NUCs or PCs not RPis.
Yes, they are right: if you use a RPi use a SSD and a faster SSD that can get.
The main issue with taking long time to catch up blocks after restart you can see it yourself by looking into bitcoin logs, through SSH:
cd umbrel
docker-compose logs bitcoin
Then you will see that it stay long time to find a good peer to catch the blocks. It has NOTHING to do with your internet speed, disk speed, machine speed. It just wait for a good peer.
As you can read in that guide about running in hybrid mode there are more chances to catch good peers faster.
Once the peers are found you will see in logs that the sync go smooth, no need to panic that your node is having any issues.