Inversion means the market expects rates to fall in the future, usually because it expects the economy to weaken. Every US recession since the 1970s was preceded by a 2s10s inversion, but the lag has ranged from six months to two years, and the curve typically un-inverts before the recession starts.
It is a macro backdrop, not a trading signal with a timestamp.
Example: the 2s10s spread inverted in July 2022 and stayed inverted for over two years, the longest on record, while stocks made new highs.
Related: yield-curve, federal-funds-rate, gdp, risk-on-risk-off