Hi Paul . . .
Welcome to -- Ireland Reaching Out . . . .
Thank you for your query . . . which is very light on Irish info. . . .
I searched on " Roots " (paid) . . a very reliable search engine . . .
Given the info. you gave . . Scanlan - 1816 - Ardfinnan - Tipperary . ..
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I searched " Tipperary " only . . . and got 3 (only) hits . . . for Thomas . . . between 1811 - 1821 (see below )
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These three Thomas's . . . are in the general area of . . Ardfinnan . . . (see map below )
If Ardfinnan is at the base of the Map . . . then Clonmel and Cahir . . . are in a reasonable distance to Ardfinnan . . .
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I checked . . . the R.C. . . Parish . . for Ardfinnan . . . https://registers.nli.ie/parishes/1089 . . .
which would confirm that a Church ( with records) was established there . . in the early 1800 . . .
which begs the question . . . why would your Thomas . . . be Baptised in Clonmel // Cahir .. . which leads to a conundrum . . .
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Next I looked at the " Townslands " of Ardfinnan . . . and found . . . Killaidanmee 136 A, 0 R, 4 P
https://www.townlands.ie/tipperary/ardfinnan2/
which would appear to be close to what you gave . . .
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Death . . . ( see below ) . . . which confirms your info.
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Next I searched a Property Tax Roll . . . Griffiths Valuation . . (1847 - 1864 )
There was NO listing for Thomas . . . which would seem to indicate . . . he was not a Farmer // Property owner . ..
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Next I searched the National Census of 1901 . . . for a Scanlan Family . . . for that area . . . NO joy . . .
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Next I searched for a MARRIAGE . . . timeline . . . 1830 - 1850 . . . Tipperary . . . (see below)
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So Paul . . .
Best I could do . . . take your pick !!
Best of good luck with your continued searching . . .
Cheers from Ireland . . . Eamonn.