There is no guarantee that our new algorithms match Geocaching.com all the time. But we believe they should be correct, according to the data at least.
I did some fast digging on your statistics.
Your 18,000th according to Project-GC is this one:
18000 2021-08-07 231 days Lab Cache The Director's son was a missionary
I then extracted all your finds for that date, in the order that the current Milestones-list uses them (after our recent changes). It looks like this:
# logId gccode created-at logged-at
18000 3021312946 2021-08-07 15:17:01 2021-08-07 15:17:01
18001 3021312958 2021-08-07 15:17:29 2021-08-07 15:17:29
18002 3021312968 2021-08-07 15:17:50 2021-08-07 15:17:50
18003 3021312976 2021-08-07 15:18:18 2021-08-07 15:18:18
18004 3021312982 2021-08-07 15:18:38 2021-08-07 15:18:38
18005 1040049489 GC9DH1D 2021-08-07 21:36:21 2021-08-07 08:15:00
18006 1040051221 GC96PZB 2021-08-07 21:44:44 2021-08-07 12:00:00
18007 1040051794 GC9EJE6 2021-08-07 21:47:53 2021-08-07 12:00:00
18008 1040052674 GC9EKKG 2021-08-07 21:52:58 2021-08-07 12:00:00
18009 1040052950 GC9EKKH 2021-08-07 21:54:44 2021-08-07 12:00:00
18010 1040053287 GC9EKK0 2021-08-07 21:56:40 2021-08-07 12:00:00
18011 1040053596 GC9EKK8 2021-08-07 21:58:24 2021-08-07 12:00:00
18012 1040054162 GC9EKJV 2021-08-07 22:01:18 2021-08-07 12:00:00
18013 1040054457 GC9EKJC 2021-08-07 22:03:05 2021-08-07 12:00:00
18014 1040055150 GC9EKJG 2021-08-07 22:07:21 2021-08-07 12:00:00
18015 1040055708 GC81DX7 2021-08-07 22:10:35 2021-08-07 12:00:00
18016 1040057377 GC9E5HX 2021-08-07 22:20:44 2021-08-07 12:00:00
18017 1040057804 GC9DAPR 2021-08-07 22:23:47 2021-08-07 12:00:00
The same data on an external link using monospace font for more readable formatting:
https://pastebin.com/t4PmQ6QU
As you can imagine those without gc-codes are Lab caches (the logIds are also "fake", they don't match any real ID, but it's irrelevant). The only event in that list is GC9DH1D.
According to the data, which we receive from Geocaching.com, the logs on the lab caches were created before the logs on the event and the other geocaches were. If this isn't true, I would assume that's a bug in either the apps creating the logs or in Geocaching.com's system. Could be a timezone issue for example. But from what I can see, the lab caches were logged before the geocaches.
PS! We appreciate hearing about things like this now when we have updated the milestones code. There could very well be issues and the only way to know is to try to verify data manually.