Bug Report: BO3 Timeless Matches Only Allow 6 Sideboard Cards Instead of 15

Game Mode:
Timeless, Best-of-Three (Traditional Ranked or Traditional Play)

Issue Description:
In Best-of-Three Timeless matches, the game restricts players to only 6 sideboard cards instead of the intended 15. This appears to be a severe miscalculation of sideboard rules, as even Best-of-One formats typically allow 7 cards.

Timeless, as a Constructed format, should follow traditional BO3 sideboard rules permitting 15 cards. Currently, the 6-card limit makes competitive sideboarding impossible.

Steps to Reproduce:

Prepare a Timeless deck with 15 sideboard cards

Enter any Traditional Timeless queue (Ranked or Play)

Attempt to sideboard after Game 1 - only 6 cards are available

Expected Behavior:
Full access to 15 sideboard cards during BO3 sideboarding phases.