I have been having some strange errors when using org-agenda.  The 
errors seem to have begun about the time I upgraded to org 9.5 from the 
elpa repo a couple of weeks ago.  When I activate org-agenda, I get the 
usual menu.  When I press 'm' to search for a tag and then enter a known 
tag name, I get an empty *Org Agenda* buffer and an error in the minibuffer:


Symbol’s value as variable is void: timestamp-up


With debug-on-error set, I get the following backtrace:


Debugger entered--Lisp error: (void-variable timestamp-up)
   org-entries-lessp(#("  ubuntu:     Updated Pop_OS (Ubuntu) ..." 0 14 
(type "tagsmatch" priority 1000 ts-date nil todo-state$
   sort((... ... ... ... ... ... ... ... ... ... ... ... ... ... ...) 
org-entries-lessp)
   org-agenda-finalize-entries((... ... ... ... ... ... ... ... ... ... 
... ... ... ... ...) tags)
   org-tags-view(nil)
   funcall-interactively(org-tags-view nil)
   call-interactively(org-tags-view)
   org-agenda(nil)
   funcall-interactively(org-agenda nil)
   call-interactively(org-agenda nil nil)
   command-execute(org-agenda)

When I enter org-agenda and use 'a' for my agenda, I get the following 
error:


Invalid function: (date date)


And the backtrace is:


Debugger entered--Lisp error: (invalid-function (date date))
   (date date)()
org-agenda-get-day-entries("/home/wdmccoy/orgfiles/C/C-examples.org" (10 
18 2021) :deadline :scheduled :timestamp :sexp)
   apply(org-agenda-get-day-entries 
"/home/wdmccoy/orgfiles/C/C-examples.org" (10 18 2021) (:deadline 
:scheduled :timestamp :s$
   org-agenda-list(nil)
   funcall-interactively(org-agenda-list nil)
   call-interactively(org-agenda-list)
   org-agenda(nil)
   funcall-interactively(org-agenda nil)
   call-interactively(org-agenda nil nil)
   command-execute(org-agenda)


If I start  emacs with the -Q switch and then execute my 
org-agenda-files setting command in the *scratch* buffer:


(setq org-agenda-files (directory-files-recursively "~/orgfiles/" 
"\\.org$"))


then org-agenda appears to work fine without errors.  So I have made a 
minimal init.el file and trimmed virtually everything from my 
emacs-custom.el file (file attached), but the error returns.  I just 
can't figure out what's causing it.  Any ideas?


Thanks, Bill