“one must ask oneself: ‘was what the taxpayer did a reasonable thing for a responsible trader conscious of and intending to comply with his obligations regarding tax, but having the experience and other relevant attributes of the taxpayer and placed in the situation that the taxpayer found himself at the relevant time, a reasonable thing to do?’”
“a notice or form which is to be served under the Taxes Acts on a person may be either delivered to him or left at his usual or last known place of residence.”
“…. unless the contrary intention appears, service is deemed to be effected by properly addressing, pre-paying and posting a letter containing the document and, unless the contrary is proved, to have been effected at the time at which the letter would be delivered in the ordinary course of post .”