Short answer

• Samvatsari Pratikraman is tied to the Samvatsari tithi itself. As per traditional maryada, it is not shifted to another date like Dubli Atham.
• If you are in rajasvala (periods/asauch), do not sit in the formal Pratikraman. Keep the bhav on Samvatsari itself (kshamāpanā/Micchhāmi Dukkaḍaṃ), and then, after śuddhi, do alochanā–pratikraman at the earliest suitable time as a niyam you have taken beforehand (pachchakkhān).

How to observe correctly in this situation (simple, tradition‑safe)

• On Samvatsari day itself:

- Maintain ahimsā, carefulness, and food niyams as health allows (e.g., ekāsan/biyāsan or light upvās if your health permits). - Recite Navkār Mantra with bhaav and do quiet kayotsarg (mental repentance). - Offer kshamāpanā to all (Micchhāmi Dukkaḍaṃ) on that day itself.

• Take a clear pachchakkhān: “After śuddhi I will perform the full alochanā–pratikraman at the earliest opportunity.” Then complete it after your śuddhi. In many sanghs this is done on the first clean day, or at the next pakshik/chaumāsī sitting, as guided by your guru.
• Do not move the “Samvatsari” itself to Dubli Atham; instead, you “make up” the formal recital after śuddhi under your local maryadā.

Notes by tradition

• Shvetāmbara: The annual Samvatsari is fixed to that tithi. During rajasvala one refrains from the formal avashyaks; bhāva‑pratikraman, kshamāpanā, and later alochanā–pratikraman after śuddhi are advised.
• Digambara (Daśalakṣaṇa/Kshamāvaṇī): Same principle—do kshamābhāvanā on the forgiveness day; complete the formal anushṭhān after śuddhi per ācārya‑maryadā.

If your local ācārya/sangh has a written maryadā allowing listening from a distance or a specific “make‑up” arrangement, follow that. Otherwise, keep the bhāva on Samvatsari and complete the formal pratikraman after śuddhi; do not reschedule it to Dubli Atham.

For simple guidance on Pratikraman and Paryushan:

• Pratikraman basics
• Why Paryushan/Samvatsari is observed