Chris Cunningham uploaded a new version of Chronology-Core to project The Inbox:
http://source.squeak.org/inbox/Chronology-Core-cbc.45.mcz

==================== Summary ====================

Name: Chronology-Core-cbc.45
Author: cbc
Time: 14 May 2019, 3:33:13.333275 pm
UUID: 4117cd16-a46a-4647-9630-49ee93d3f725
Ancestors: Chronology-Core-nice.44

With the UTC / DateAndTime changs, DateAndTime>>utcOffset: changed to update the existing instance in place instead of creating a new instance.
The change fixes #asLocal to create a new instance, bypassing #utcOffset:.
Follows the same logic as used in #asUTC

=============== Diff against Chronology-Core-nice.44 ===============

Item was changed:
  ----- Method: DateAndTime>>asLocal (in category 'ansi protocol') -----
  asLocal
+ 	"Anwer a copy of oursielves (if necessary) in the local timezone.  #utcOffset: now modifies my instance, so the creation of the new instance should happen here."
- 	
  
  	^ (self offset = self class localOffset)
- 
  		ifTrue: [self]
+ 		ifFalse: [self copy localOffsetSeconds: self class localOffset asSeconds]!
- 		ifFalse: [self utcOffset: self class localOffset]!