If a person is not from Schengen area (for example Ukrainian, Russian, Bhutanese citizen), they all have similar visa conditions.
Estonian Pema Lingpa religious organisation can invite religious teachers, monks, and nuns for longer period.
All the persons from above-mentioned countries fall under the residence permit quota: that is to say, only certain number of long term residence permits is given out every year.
This type of residence permit can only be applied in December and January (time for appointment has to be booked earlier, in October or November, as soon as the submitting of applications opens). When the time is booked, this person has to personally present himself/herself in the migration office or foreign consulate of his/her country.
The processing of the application takes two months usually and when the positive decision is made, the person does not need to go herself/himself to collect the permit card, somebody with his/her consent can do it (it has to be mentioned in the papers when the application is given).
The residence permit can be given for five years (this is what should be applied for) but they never give it for that long for the first time. Usually they give it for one or two years. Then the permit can be prolonged online, no need to go in the office.
This means that for the persons from above-mentioned countries the only possible starting time of the retreat is around March, when the positive decision is made about the residence permit.
They can come to Estonia for a short, one-year residence permit (living and work permit, but for monks and nuns, there is no need to give a salary). This can be done online and does not fall under the quota. But the problem with this short-term permit is that when one year is done, the same type of permit cannot be prolonged immediately, the person has to stay out of the country for a certain period.
However, with this permit (if she/he came here with that) she/he can apply for a long-term residence permit (which was described above).
More information about the residence permit procedures is found at https://www.politsei.ee/en/instructions/residence-permit-card-for-an-adult
The letters of invitation have to be approved in the ministry of interior affairs. Invitation letters have to be done by the Estonian religious association of Pema Lingpa.