All owners are reminded to look their rosters over to make sure that they will be able to field a complete lineup for week #1.
You will have the one pre-season move to help you fill a position if needed. Most likely you won't be able to use the DL until week #1 as most MLB clubs do not place their players on the official MLB DL list until the day of their first game. OGBL rules state that for a player to be placed on your DL he must first be on the MLB DL.
To field a complete lineup you may need to do an Add/Drop (waiver claim). You can put in a waiver claim from Monday, March 30th through Saturday, April 4th.

Waiver Results for Pre-Season Add/Drops,
Monday - Results Wednesday Night
Tuesday - Results Wednesday Night
Wednesday - Results Wednesday Night
Thursday - Results Thursday Night
Friday - Results Friday Night
Saturday - Results Saturday Night
Sunday - No Roster Moves Allowed

This will be the same for the regular season with the exception of Sunday. It will read,
Sunday - Results Sunday Night

The above info is how I have the waiver wire set. If you are positively going to make a waiver claim it might be wise to put it in early if you want a certain player who just might be popular.
The draft order (starting with Kelly's Heroes) will be the the order for the pre-season waivers.

Jimi ... for the preseason waiver claim, does it matter when the claim comes in? Will all claims before the final deadline be parsed out based on draft order?

Barry, the waiver claims go in reverse order and is reset each week. Once a team has successfully claimed a player they will move to the bottom of the order.
Owners can put claims in from Monday through Wednesday with the results coming Wednesday night. On the other days the results come each night.
Yes, all claims will have results before the final deadline. The pre-season waivers work a little different as there is only one claim be team allowed. Starting week #1 though week #10 there is no limit on add/drops.
I'm not sure I answered your questions correctly, if not maybe a phone call would work better. I get home around 4:00 PM PT M-F.

Jimi, what do you mean, you get home at 4 PT? Did you give up the Mr. Mom title and get a job?

You caught that Earl, I did go back to work. I managed to hook on with a company that I have worked for in the past.
I needed to get back to it as my dental & medical are about to run out. I ran my banked hours dry with my 4 month vacation.

so ... what ya doing?

Barry, pretty much the same thing I've been doing the past 28 years, commercial interior construction, Specializing in acoustics.
It's a Hospital addition going on in Sacramento.