SSIS Pre Validation taking a long time - only on server

Question

I have an (SQL Server 2017) SSIS package that takes about 5 seconds to run in Visual Studio 2019, and a similar amount of time to execute after being deployed to my local database server - on my development computer. However, when I deploy it to another server, and run it, it takes about 26 seconds to run. When looking at the execution reports - almost all of the extra time is spent in the pre-validation phase in one step

The two log entries are the first two messages in the log, and the first one is for the pre validation of the whole package. All the rest of the entries look similar to those I see on my development server.

One other note: I had previously deployed this package to this server without this same issue. I then added two tasks. One to pull xml into a result set, and another to email the results of the package. Although one of the them does load an external dll to do the emailing, neither of these two tasks take more than a second to validate or execute.

Anybody have an idea of why I would see a 20 second delay on the package pre-validate - but only on another server - and how I might be able to get rid of it?

Further Note: I re-deployed an earlier version without the latest changes, and the 20 seconds went away. Then step by step I added the functionality back. The 20 seconds did not come back.

So just to validate this, I re-built the current version (that originally had the problem) and deployed it... and it is now back to taking 5 to 6 seconds to execute!

It could be the re-build, or it could be that that server had just been re-booted. I don't know!

I will leave this question open for a day or two to see if it comes back.