I tried the first find/replace you suggested but it didn't remove the numbers.
I'm sorry I didn't post enough at the start to fully explain my issue. It wasn't until I started to try and fix it and I got into the edit book function (it's not an area I usually play in).
I've been reluctant to post too much because of copyright concerns.
You said "Not enough code for the second part: for removing the <br class="calibre1"/>"
Is this enough?
</head>
<body class="calibre">
<p class="calibre_"><span class="calibre2"><span class="bold">Ten</span></span></p><p class="calibre_"><span class="calibre_1">09</span><br class="calibre1"/><span class="calibre_1"> 10</span><br class="calibre1"/><span class="calibre_1"> 11</span><br class="calibre1"/><span class="calibre_1"> 12</span><br class="calibre1"/>
<span class="bold">“So this is </span>the famous <span class="italic">Joooooooo-nah</span>,” Liz says, subtle as a light<span class="calibre_1">13</span><br class="calibre1"/> ning strike. She shifts her white wine into her other hand so she <span class="calibre_1">14</span><br class="calibre1"/> can shake Jonah’s. All around us, family friends and Chloe’s pals <span class="calibre_1">15</span><br class="calibre1"/> mill around in cocktail dresses and suits; Christmas music plays <span class="calibre_1">16</span><br class="calibre1"/> just loud enough to be heard amid the buzz of the crowd. Liz’s grin <span class="calibre_1">17</span><br class="calibre1"/> is brighter than the chandelier overhead. “I’ve heard so much <span class="calibre_1">18</span><br class="calibre1"/> about you, Mr. Marks! Can’t wait to find out if it’s true.”
Same text in live preview:
Ten
09
10
11
12
“So this is the famous Joooooooo-nah,” Liz says, subtle as a light13
ning strike. She shifts her white wine into her other hand so she 14
can shake Jonah’s. All around us, family friends and Chloe’s pals 15
mill around in cocktail dresses and suits; Christmas music plays 16
just loud enough to be heard amid the buzz of the crowd. Liz’s grin 17
is brighter than the chandelier overhead. “I’ve heard so much 18
about you, Mr. Marks! Can’t wait to find out if it’s true.”
Note: This is after I have done the find/replace with <span class="calibre_1">\d+</span>\s