I don't think you can read anything in terms of victory by the rise in Republican early voting, it's very possible if not likely that they are just converting election day voters to early voters with no net increase to the pool.
However, it does have a couple positive signs for Republicans. First, the "we won't early vote" thing for Republicans was a massive self-own and a handicap. That trend was simply moving their tee further back from the Dems to start. Even if it doesn't mean they're reaching new voters, starting without that handicap is huge in a close race.
Also, there was a LOT of hand wringing my smart Rs about how awful the Republican operations were on the ground at the state level, in terms of GOTV, getting absentee ballots out, etc. All kinds of reports of the ground games being cash broke, ineffective, etc. Early voting returns seem to indicate that either the ground game wasn't as f-cked as reported, or they got it funded and organized in the last weeks, OR it really is a mess and doesn't matter because Republican enthusiasm is overwhelming. If it's the latter, that's almost the best news for Rs.
This race is still a toss up, but my read is that it's clearly broken slightly in Trump's direction in the last week or so. I think that's what Harris' inside numbers are showing, and I think it's very obvious if you watch the Harris campaign. The Harris attempt to appeal to dissatisfied Rs and center-right independents (and men, working class, et seems over and unsuccessful. Polls show that Trump's slight improvement in polls is primarily from solidifying the support of republicans from like 85% to 95%. Kamala tried, but just whiffed with that group.
Those ads are still running, but at the national messaging level, Democrats have totally abandoned positive and persuasive messaging, and pretty much exclusively speaking to the base. They are ramping up the Hitler/fascist talk again, something that is proven unpersuasive to swing voters, and they are browbeating their non-white blocks and accusing them of sexism for not voting Kamala. I think clearly the read that the Harris campaign is getting is that they don't have a working message for the undecided or Trump-sympathetic voter, and they need to max out their base.
And one totally personal observation I haven't seen mentioned. Living in a swing state...the Harris advertising is getting decidedly weird in the last week. Not exclusively weird, but especially in digital ads like one out of 5 or 6 Harris ads are...really bizarre? Like in a "how do they think this is going to help?" kind of way. To me that might signal some "try anything" desperation at play. I don't think they are desperate in terms of being sure they will lose, but desperate that they have not been able to separate at all and are still in a coin flip.