Yes, this is an example where, due to Vocab still being a Beta feature, some vocabs have confused or flipped/switched definitions or readings.
In this case, there are three readings for 先 as a vocab. Using the browser extension 10ten Japanese Reader (I’m using Firefox), I’ll quickly copy those entries from Jisho/JMdict:
先, 前, 先き [さき]
(1) (n) point; tip; end; nozzle
(2) (n) head (of a line); front
(3) (n) first; before; ahead (of)
(4) (n) (the way) ahead; beyond
(5) (n,adj-no) future
(6) (adj-no,n) previous; prior; former; recent; last
(7) (n,n-suf) destination; address; place where you do something
(8) (n) rest (e.g. of a story); continuation; remaining part
(9) (n) the other party
先 [さっき]
(n,adv) (uk) a short while ago; a moment ago; just now; some time ago
先 [せん]
(1) (adj-no,n) former; previous; old
(2) (n) first move (in go, shogi, etc.); opening move
As you can see, there are three main readings: さき, さっき, and せん. And each has a distinct cluster of meanings.
In particular, 先 (さき) can mean either “previous; prior; former; recent; last” or “ahead; beyond” or even “future”. Seemingly it can mean ‘past’ or ‘future’ depending on context.
On the other hand, 先 (せん) can only mean “former; previous; old”, so seems restricted to only ‘past’.
In this case, although there are 3 dictionary entries for the vocab ‘先’, there is only 1 Vocab entry for ‘先’ on Bunpro.
And so, it seems that this Bunpro Vocab has a bit of a mixed-up/confused identity. On the one hand, its reading is さき, and the Example Sentences have meanings of ‘ahead’ and ‘future’. So, it appears that the Sentences line up with the specific reading さき. But the listed definitions seem more in-line with the dictionary version of 先 with reading せん.
There are numerous examples of such Vocab confusions, mixing different things from readings/furigana, to definitions, to sentence usages, etc.
When I find such mix-ups, I often submit a bug report with the Report [] button, explaining what’s confusing and offering a resolution. For example, in this case, I would suggest that the definitions on the item page should be replaced with ones more in-line with the sentences and the reading さき, rather than せん.
Hopefully, as they work through the Vocab decks, they will be able to comb through them all and clean/tidy them up.
Honestly, 先 is an N5 Vocab, so it looks like this one slipped through, though.