Short, direct answer:

• A person born on the first day of the 5th āra (Pancham kāl) cannot attain moksh in that same birth from Bhārat Kṣetra.
• A person born on the last day of the 4th āra (Chaturth kāl) can attain moksh in that same birth, if all other spiritual conditions (samyak-darshan, right conduct up to the highest levels, complete kashāya-kṣaya etc.) are fulfilled.

Now in simple traditional terms:

1. Where can moksh happen in the time-cycle?

- In Bhārat Kṣetra of the current avasarpinī, - Tirthankars and Kevalis arise, and moksh is attained only in 3rd and 4th āra. - From the very first moment of 5th āra, no new Kevali and no moksh occur from Bhārat (and Airāvat) Kṣetra. This is accepted by both Digambar and Śvetāmbara traditions.

1. Border between 4th and 5th āra

- At the last instant of 4th āra, the era still has the spiritual capacity for keval-jnān and moksh. - At the first instant of 5th āra, that capacity ends for Bhārat Kṣetra. So the deciding factor is not “date” in our calendar, but which āra the birth and the life fall into.

1. Applying this to your two cases

(a) First day of 5th āra - Era = Pañcham kāl (Duḥṣamā). - Scriptural rule: in 5th and 6th āra of Bhārat, no Tirthankar, no new Kevali, no moksh. - So, a person born then cannot attain moksh in that same birth from Bhārat Kṣetra, even if they practice very intense sādhana. They create causes for future liberation (e.g., rebirth in Mahāvideh Kṣetra), but not moksh “right here, right now.”

(b) Last day of 4th āra - Era = Chaturth kāl (Duḥṣamā–Suṣamā), which still allows appearance of Tirthankars, Kevalis and moksh. - Therefore, yes, if someone is born then and progresses to samyak-darshan, full right conduct and total destruction of ghātiyā karmas, they can attain moksh in that same birth. - Bhagwān Mahāvīr’s nirvāṇa itself is traditionally placed at the very end of 4th āra, illustrating that moksh is possible up to the final moment of that era.

1. Digambar–Śvetāmbara note

- Both agree on the principle: - Moksh in Bhārat Kṣetra during 3rd–4th āra only. - No moksh from Bhārat in 5th–6th āra. - They differ only in some historical dating details (exact year count of Mahāvīr’s nirvāṇa, etc.), not in this core rule.

So, summarizing again very simply:

• First day of 5th āra → moksh in the same birth from Bhārat Kṣetra: NO.
• Last day of 4th āra → moksh in the same birth from Bhārat Kṣetra: YES (if full moksh-mārg is completed).