As most of you know, MLB is planning to implement a few rules changes in 2020, one of which is the addition of a 26th man (who cannot be a pitcher) to the active list rosters Opening Day through August 31st. 

12/2 UPDATE:

The Cubs have tendered 2020 contracts to all unsigned players on their MLB 40-man roster except LHRP Danny Hultzen and INF Addison Russell, and RHP Jharel Cotton has agreed to a $640K 2020 non-guaranteed contract to avoid being non-tendered (see ORIGINAL POST below for the reasons).  

So Hultzen and Russell have been removed from the Cubs MLB 40-man roster and both are now unrestricted free-agents, free to sign a major league or minor league contract with any club, including the Cubs.
NOTE: The Cubs MLB Reserve List now stands at 36 (four slots are open).

It's likely that the Cubs have tentatively agreed (in advance) to sign Hultzen to a minor league contract after the Rule 5 Draft (with an NRI to Spring Training and for more money than he would have received if he had remained on the 40 -- as happened with Allen Webster a year ago) - AS LONG AS - Hultzen does not receive an MLB contract offer (which would include a slot on an MLB 40-man roster) for even more money from another club in the interim (which is exactly what happened after the Cubs non-tendered Ronald Torreyes a year ago), or a substantial salary offer from an NPB (Japanese) club (as happened after the Cubs non-tendered Justin Hancock last year).   

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11/26 ORIGINAL POST:

It wasn't exactly A Day that Will Live in Infamy, but a year ago today the Cubs traded Tommy LaStella to the Angels for a PTBNL (who turned out to be LHRP Conor Lillis-White). 

LaStella was one of the best pinch-hitters in the National League and had one of the best single-seasons of pinch-hitting in Cubs history in 2018 (312/396/416 with 5 2B, 1 HR, 11 RBI, 2 HBP, 9/13 BB/K in 79 PA with an MLB-leading and Cubs single-season club record 24 pinch-hits), and then he hit a robust 295/346/488 with 16 HR in 80 games for LAA this past season (where he was the Angels' everyday 2B for the first half of the campaign, before missing the second half after suffering a broken leg on 7/2). 

However, despite trading LaStella, the Cubs did have four of the better pinch-hitters in the National League (including two of the top six) in 2019. 

The Cubs have claimed LHRP Christian Devont'a (C. D.) Pelham off waivers from the Texas Rangers.

The 24 year old 6'6 235 lefty was a 33rd round draft pick of the Texas Rangers out of Spartanburg Methodist JC ($40,000 bonus) in 2015 (he was also selected in the 25th round of the 2014 draft by the Milwaukee Brewers but did not sign).

Pelham features a mid-90's (T-98) CT FB and a power slider, but has had control issues throughout his career (kind of like another big lefty reliever the Cubs acquired a few months ago, Brad Wieck), especially in 2019 (40 BB in 32.1 IP split between AA and AAA). 

Pelham was rated one of the Rangers Top 15 prospects by Baseball America post-2018 and he pitched in the Futures Game in July of that year. 

The Cubs have acquired the contract of RHP Jharel Cotton from the Oakland Athletics in exchange for cash considerations (probably something in excess of the $50,000 waiver price).

Cotton was Designated for Assignment by the A's last Wednesday. 

11/20 UPDATE:

The Cubs have selected the contracts of RHSP Tyson Miller and SS Zack Short from AAA Iowa and RHRP Manuel Rodriguez and C Miguel Amaya from Hi-A Myrtle Beach, and all four have been added to the Cubs MLB Reserve List (40-man roster).  

So with the four additions, the Cubs MLB 40-man roster now stands at 36 (four slots are open). 

The next date of note is December 2nd (MLB Contract Tender Deadline).  

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11/10 ORIGINAL POST: 

15 Cubs minor leaguers were declared MLB Rule 55 minor league free agents at 5 PM (Eastern) Monday 11/4.