Answer

No. 1 Ayambil and Ekasana are not exactly the same.

Explanation

Ekasana means eating only one time in one sitting during the day, with proper Jain discipline.

Ayambil is also usually done as one sitting, but it has stricter food rules:

• Food must be very simple and tasteless.
• No milk, curd, ghee, oil, sugar, jaggery, spices, fruits, vegetables, or rich foods.
• Usually plain boiled grains/pulses are taken.
• The focus is on reducing taste attachment.

So, Ayambil includes the discipline of one-time eating, but it is stricter than Ekasana.

Takeaway

Ekasana = one sitting meal.
Ayambil = one sitting meal with very strict tasteless food discipline.