catched by @kyrylogy

I believe the issue lies here and here

tmpDirs=hadoop fs -ls ${hdir}/$year/$month | grep tmp$ | awk '{print $8}' | sed -e "s,\.tmp,,g" -e "s,${hdir},,g"
This gives us the date of .tmp file, which is the file of the day - on 1st of the month it would give /2022/08/01

lastSnapshot=hadoop fs -ls ${hdir}/$year/$month | egrep -v ${pat} | tail -1 | awk '{print $8}'
Here we get the same list of files, but without todays date. Then we take the path of last file - on 1st of the month it would pop the only available file. Additionally, we only apply it to current month's list of data, so there's no file behind the first file of current month.

I will fix it

Thanks @kyrylogy , it would be great!

Fixed by #109