Mae’r gwaith modelu'n amhendant ond y ffactorau a ddylai lywio ein penderfyniadau ar natur cyfnod atal byr yw:dylid ei weithredu cyn gynted â phosibl gan gydnabod yr angen am rywfaint o ymgynghori a chyfathrebu angenrheidiol i baratoi sectorau a'r cyhoeddcyfnod o bythefnos yw'r cyfnod lleiaf sy'n debygol o gael effaith; po hiraf yw’r cyfnod y gorau fydd yr effaithmae’r neges syml o aros gartref yn fwy tebygol o gael ei deall a'i monitro'n haws na chyfyngiadau mwy cymhleth ar deithio daearyddoldylem sefydlu eithriadau addas sy'n caniatáu i'r cyhoedd barhau i ymgymryd â gweithgarwch corfforol, cymryd rhan mewn gweithgareddau awyr agored risg isel, a chefnogi aelwydydd un person a rhieni senglbyddai'n ddoeth galluogi plant iau a phlant sy'n agored i niwed o oedran ysgol uwchradd i aros yn yr ystafell ddosbarth, gan gefnogi rhieni sy'n weithwyr allweddol. Mewn ysgolion uwchradd ac annibynnol, byddai'n ddoeth i'n plant ieuengaf a'n plant mwyaf agored i niwed barhau i dderbyn addysg wyneb yn wyneb. Ar gyfer plant hŷn mewn ysgolion uwchradd ac addysg bellach, bydd parhad yr addysgu drwy ddulliau ar-lein yn lleihau unrhyw darfu ar addysg ac ar yr un pryd yn lleihau rhyngweithio cymdeithasol, yn unol â diben y cyfnod atal byrbydd prifysgolion sy'n aros ar agor hefyd yn atal canlyniadau andwyol yn sgil myfyrwyr yn mudo ar raddfa fawr i wahanol rannau o'r DU a Chymru
Modelling is imprecise but the factors which should guide our decisions on the nature of a 'firebreak' are:it should be implemented as soon as possible while recognising the need for some consultation and the necessary communication to prepare sectors and the publica two week period is the minimum duration which is likely to have an impact; the longer the duration the greater the effectsimple message of staying at home  is likely to be more easily understood and monitored than more complex restrictions on geographical travelwe should maintain suitable exemptions which allow the public to maintain physical activity, engage in low-risk outdoor activities, and support single person households and single parentsenabling younger children and vulnerable children of secondary school age to remain in the classroom is advisable to support parents who are key workers.  In secondary and independent schools enabling our youngest and most vulnerable children to continue to receive face to face learning is advisable. For older children in secondary school and further education, continuity of teaching via on line platforms will minimise disruption for learning and at the same time minimise social interaction, in line with the purpose of the firebreakuniversities remaining open will also prevent the adverse consequences of mass migration of students to different parts of the UK and Wales