Thank you Lal.
‘..If he/she does not attain Arahanthood there, he/she will be born in a higher realms(s) and attain Nibbana in the future,…’
that is, depending on his /her striving in the future (after that deva bhava). I understand. Not that that deva bhava will be his/her last bhava in sansara ,having of necessity attained Arahanthood there.
Boundless gratitude for all your compassion,
y not