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2 added "ands" for clarity; changed "any" to "all" for clarity
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You do not need a Transit visa if:

You have an Indian passportpassport; and

you arrive and depart by air have a confirmed onward flight that leaves on the day you arrive or before midnight on the day after you arrive have the right documents for your destination (eg a visa for that country); and

you’re traveling from the Republic of Ireland and it’s less than 3 months since you were last given permission, on the basis of holding a valid Irish biometric visa, to land or be in Ireland

(GOV Website)

If you do not meet anyall of these requirements, you will need to apply for a Visitor in Transit Visa.

You do not need a Transit visa if:

You have an Indian passport

you arrive and depart by air have a confirmed onward flight that leaves on the day you arrive or before midnight on the day after you arrive have the right documents for your destination (eg a visa for that country)

you’re traveling from the Republic of Ireland and it’s less than 3 months since you were last given permission, on the basis of holding a valid Irish biometric visa, to land or be in Ireland

(GOV Website)

If you do not meet any of these requirements you will need to apply for a Visitor in Transit Visa.

You do not need a Transit visa if:

You have an Indian passport; and

you arrive and depart by air have a confirmed onward flight that leaves on the day you arrive or before midnight on the day after you arrive have the right documents for your destination (eg a visa for that country); and

you’re traveling from the Republic of Ireland and it’s less than 3 months since you were last given permission, on the basis of holding a valid Irish biometric visa, to land or be in Ireland

(GOV Website)

If you do not meet all of these requirements, you will need to apply for a Visitor in Transit Visa.

1
source | link

You do not need a Transit visa if:

You have an Indian passport

you arrive and depart by air have a confirmed onward flight that leaves on the day you arrive or before midnight on the day after you arrive have the right documents for your destination (eg a visa for that country)

you’re traveling from the Republic of Ireland and it’s less than 3 months since you were last given permission, on the basis of holding a valid Irish biometric visa, to land or be in Ireland

(GOV Website)

If you do not meet any of these requirements you will need to apply for a Visitor in Transit Visa.