Short answer, yes. Think about it like registering for a website somewhere. Sometimes it takes a bit for the confirmation email to arrive. “subscription pending” means it is waiting to finalize the link to the other instance.
It is a “side effect” of this federated network. If you subscribe to a local thread, it is instant. Going to something non-local takes a bit.
Something along the lines of “it is okay to be anxious, change is scary, but so is stagnation.”
Alternatively, “How do you eat an entire elephant? One bite at a time.”